There are many well known methods of engraving or producing images on a brick surface or other unglazed ceramic material, such as painting, molding, sand blasting, mechanical grinding, and chemical etching. All of them have one or more disadvantages: 1.) they involve hazardous or harmful materials and/or by-products in that they use highly aggressive chemicals, produce environmental pollution such as dust, or produce a high level of sound while creating the images; 2.) they leave poorly produced images that do not have contrast because they only remove brick material in making patterns in the brick's surface without following up with contrasting shades or colors; 3.) their processes are slower and inefficient, and require permanent and expensive tools for grinding and blasting, or special buildings and chambers with pollution collectors for chemical treatment; 4.) the resultant images are not long lasting because the mechanical processes make internal micro cracks and chips in the brick which contribute to long-term deterioration of the brick material, and the chemical processes result in penetration of the chemical into the porous brick material causing continuous chemical reaction long after the mark is created.
There is accordingly a need for a process for marking and engraving brick or other like ceramic material which can produce a distinctive, long lasting image in a manner that is efficient, safe, and environmentally sound.